As one example of an electric actuator for a turbocharger, a technique recited in the patent literature 1 is known.
The patent literature 1 discloses a technique of conducting an output of an electric actuator to a valve of a turbocharger through a so-called four-bar linkage.
The four-bar linkage includes: an actuator lever, which is fixed to an output shaft of the electric actuator; a valve lever, which is fixed to a valve shaft that is rotated integrally with the valve; and a rod, which conducts a rotational torque of the actuator lever to the valve lever.
According to the technique of the patent literature 1, the actuator lever is disadvantageously freely rotated relative to the output shaft at a stage before fixing of the actuator lever to the output shaft. Specifically, there is a disadvantage of that a fixation angle of the actuator lever relative to the output shaft cannot be determined.
In the state where the fixation angle of the actuator lever is not determined, when the actuator lever is fixed to the output shaft, variations in the rotational range of the actuator lever will occur. Thereby, variations in a link ratio of the four-bar linkage will occur. Thus, operability of the valve provided at the turbocharger will be deteriorated.
It is conceivable that the fixation angle of the actuator lever relative to the output shaft is determined by using a key groove or a width across flats, in order to avoid the above disadvantage.
In such a case, an installation angle of the electric actuator relative to the turbocharger and a positional relationship of a valve shaft provided to the turbocharger are determined.
Therefore, versatility of the electric actuator is deteriorated. That is, in a case where the installation angle of the electric actuator relative to the turbocharger is changed, it is required to change the design of the electric actuator. Similarly, in a case where the position of the valve shaft is changed, it is required to change the design of the electric actuator.